Chapter 15 - Electric Charge, Forces, and Fields - Learning Path Questions and Exercises - Exercises - Page 556: 7

$+5.15\times10^{-11}C$

The charge on 1 electron =$-1.6\times10^{-19}C$ The electroscope will acquire the opposite of the charge lost due to electrons. The charge on electroscope = $+1.6\times10^{-19}\times3.22\times10^{8}C$=$+5.15\times10^{-11}C$